Supporting bar and rack



May 19, 1936. F. w. SCHMIDT SUPPORTING BAR AND RACK Original Filed June10, 1955 Mr 2 2 W 1/7))? 71/1/1/1/1/1/ Z 2 k H d f f w 4. F m F SUM- 1Patented May 19, 1936 U ITE STATES PATENT .GFFICE Ryerson & Haynes,1110.,

poration of Michigan Jackson, I.Iich., a cor- Originai application June10, 1935, Serial No.

25,826. Divided and t 1935, Serial No. 27,851

his application June 22,

3- claims. (Cl. qr-.515)

The present invention is a division of co-pending application Serial No.25,826, filed June 10, 1935, relating to improvements in Vehicle jackingstructure and is concerned with the tubular supporting bar and rackstructure. While the inven tion is primarily concerned with ratchet jackstructure and method of making the same, it has application generally toload supporting bar and rack structure with which operating pawls ordogs or other structure coact for effecting relative movement orsupporting parts against relative movement.

Chiefiy, the object of the present invention is to provide aninexpensive, durable, sheet metal bar and rack.

Another object is toprovide a rack which is particularly designed as aload supporting column for a ratchet jack.

A further object is to provide a tubular sheet metal supporting bar andrack giving maximum rigidity with a minimum amount of material.

These and other objects residing in the specific construction andcombination and arrangement of parts will more fully appear from thefollowing description and as set forth in the appended claims.

In the accompanying drawing, wherein I have illustrated the preferredform of the invention,

Fig. 1 is a vertical section of the tubular rack taken on line I-I ofFig. 4,

Fig. 2 is a side elevational view of the rack shown in section in Fig.1,

Fig. 3 is an enlarged fragmentary sectional view of the rackcorresponding to the section shown in Fig. l, and

Fig. 4 is a plan view of one end of the tubular rack.

Referring to the drawing, the bar It! is preferably of sheet metalformed in a tubular structure as shown in Fig. 4 providing a verticaljoint at I! with the vertical edge portions i4 and IS in abuttingrelation. One of the vertical faces of the bar i0, preferably the faceopposite the joint i2, has coined or stamped therein, by a power pressoperation, a rack section l8. The manner in which the rack section iscoined in the bar I0 is an important part of the present invention andwill be described with considerable detail.

In coining the rack M in the sheet metal strip from which the bar it! isfabricated, the coining dies are so constructed that the deformation ofthe material constituting the tooth elements 20 of the rack is equallydisposed uponv opposite sides of the plane of the metal strip as will beapparent from Figs. 1, 3 and 4. This gives a balanced draw of thematerial in forming the tooth elements 2c and positions the loadsupporting webs 22 with which the pawls or dogs engage in the plane ofthe metal strip from which the elements 20 are coined. Heretofore it hasbeen the practice in sheet metal racks for ratchet jacks, which havegone into commercial practice, to completely sever the metal in definingthe teeth of the rack as shown in Patent No. 1,394,263. A departure fromthis has been made by the present invention in that increased strengthand rigidity is provided by the webs 22 between each angularly disposedrib 24. This has been accomplished by leaving suificient clearance inthe coining dies so as to avoid severance of the material betweenadjacent ribs 24. Preferably sufllcient clearance is provided in thedies so that in drawing the webs 22 the reduction in stock in the ribs24 on opposite sides is sufficient to give the webs 22 considerablethickness. In practice the thickness 01' the stock constituting the webs22 may be 15% to 25% less than that of the ribs 24, however, this is amatter of die design.

' The inspection of Fig. 4 will disclose that the bar ID as shown is oftrapezoidal section although closely approaching a triangular section.Opposite vertical faces 26 and 28 of the bar III are designed at anglesless than to the vertical face in which the rack I8 is coined andconverges toward the joint ii. If desired the faces 26 and 28 may be theopposite sides of a triangleconverging to form the joint l2. However, ithas been found desirable to turn the edges It and 56 in the manner shownin Fig. 4 giving a trapezoidal section for the reason that amoresatisfactory joint I2 may be formed and a fiat guiding surfaceparallel to that of the rack I8 is found desirable in some c cases suchas for guiding the bracket attachment of the ratchet jack as shown inthe aforesaid application. As a rule, the vertical face in which therack I8 is defined will be of the greater width than the width of thesections 26 and 28 which will be varieddepending upon the strength andrigidity of the sections required. It should be readily apparent thatthe rigidity of the supporting bar and rack of the section shown in Fig.4 is more than equal that of a square section, yet requires less stockin its fabrication. Moreover, by having the faces 26 and 28 disposed atless than at right angle to the rack I8, they are capable of givinglateral support and guiding action to structure acted upon by forcesdirected, for example,

perpendicular to the face of the bar Ill in which the rack it isdefined. This characteristic of the faces 28 and 28 is being employed inthe aforesaid application to support and guide the attachment bracketand housing along the supporting bar. and rack.

The vertical edges I! and I6 of the bar structure constituting the jointl2 may be merely pressed into contiguous relationship leaving alongitudinaliy extending split or they may be welded or otherwisesuitably joined along the joint I2. It is also to be understood that thelocation of the joint l2 may vary although as above stated, it ispreferably located opposite the side of the bar structure in which theteeth are coined.

By coining or stamping the rack 18 and forming the bar ID in the mannerabove described, it has been possible to obtain the required durabilityand rigidity of construction with stock of minimum width and thicknessthus materially reducing the cost of production.

Having described my invention what I claim as new and desire to protectby Letters Patent is:

1. Abar and rack for ratchet jack structure and the like comprising ahollow sheet metal tube of substantially trapezoidal cross section, andteeth on the longer of the parallel sides of said tube.

2. A bar and rack for ratchet jack structure and I the like comprising asplit hollow sheet metal tube of substantially trapezoidal cross sectionhaving the split on the shorter of the parallel sides, and teeth on thelonger of the parallel sides of said tube.

3. A bar and rack for ratchet jack structure and the like comprising ahollow sheet metal structure closed in cross-section and having one sidewith teeth therein, and opposed sides adjacent said first named side,said opposed sides being non-parallel and converging toward each other.

FRANK W. SCHMIDT.

